Container closure

ABSTRACT

A closure for a container having a top wall, a first tubular wall with a radial exterior surface and a radial interior surface, and a second tubular wall with a radial exterior surface and a radial interior surface. The first tubular wall extends generally transversely downwardly from a peripheral edge of the top wall and the second tubular wall extends generally transversely downwardly from an interior surface of the top wall radially inwardly from the first tubular wall to establish an unobstructed void between the interior surface of the first tubular wall and the exterior surface of the second tubular wall. The interior surface of the second tubular wall has first screw threads configured to removably engage second screw threads formed on the container.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Patent Application No. 61/227,286, filed on Jul. 21, 2009, entitled “Container Closure,” the entire contents of which are incorporated by reference herein.

BACKGROUND OF THE INVENTION

Conventional safety closures for medicament containers have a double wall, double shell configuration. These conventional closures have certain dimensions that are adaptable with existing machinery for manufacturing and packaging such closures. A multiplicity of so-called easy-to-open closure mechanisms, with a double wall and double shell configuration, have also been developed and marketed in the past. Such easy-to-open closures mechanisms have been on the market for many years and are well accepted container closure designs. In essence, they are merely design modifications of conventional safety closures. In other words, these known easy-to-open closures are assembled in the same manner as conventional double wall, double shell safety closures, without a safety mechanism or with the safety mechanism disabled, such that the existing machinery for manufacturing and packaging conventional safety closures may be used.

For example, conventional safety closures include an assembly of first and second caps which rotate freely relative to each other, such that the safety closure cannot be removed from a container unless the first cap is pressed down upon or squeezed in from the sides, and brought into engagement with the second cap. In many of the known easy-to-open closures, the safety mechanisms are merely non-existent or disabled and the first and second caps are permanently secured to each other, such that the first and second caps are incapable of rotating freely relative to each other. Thus, when the first cap is rotated by a user, the second cap is correspondingly rotated, allowing the closure to be unscrewed from a container without the application of any force upon the first cap.

Such known easy-to-open closures are often bulky and expensive to manufacture, as they require a certain degree of assembly to disable the safety mechanism and to secure the first and second caps to each other. In particular, securing of the first and second caps together is often a troublesome aspect of the assembly of these prior art closures. The first and second caps must be secured together in a very sensitive manner to ensure that there is a strong bond between the two caps. If such a strong bond is not achieved, the bond can break, the first and second caps will no longer be secured to each other, and the closure is no longer operable. Thus, ensuring that a sufficient bond is achieved between the first and second caps is always a manufacturing concern for the prior art closures.

Further, a single-wall closure is not a feasible alternative to these prior art double wall closures. The single tubular sidewall of a single-wall closure would have to be of a significant thickness to efficiently serve as a container closure. However, during formation of the single-wall closure by, for example, injection molding, the level of sink associated with formation of the sidewall becomes problematic, as sink marks or voids can occur in the thick molding of the sidewall.

Thus, it is desirable to provide an integral easy-to-open double wall closure adaptable for use with a variety of containers. Eliminating the need for the assembly steps required to secure a first cap to a second cap and to ensure a sufficient bond between the two pieces results in an integral double wall closure which is readily and inexpensively manufactured.

BRIEF SUMMARY OF THE INVENTION

Briefly stated, the present invention is directed to a closure for a container. The closure includes a top wall with a peripheral edge, an exterior surface and an interior surface; a first tubular wall with a radial exterior surface and a radial interior surface; and a second tubular wall with a radial exterior surface and a radial interior surface. The first tubular wall extends generally transversely downwardly from the peripheral edge of the top wall and the second tubular wall extends generally transversely downwardly from the interior surface of the top wall radially inwardly from the first tubular wall to establish an unobstructed void between the interior surface of the first tubular wall and the exterior surface of the second tubular wall below the interior surface of the top wall. The interior surface of the second tubular wall has first screw threads configured to removably engage second screw threads formed on the container. Rotating the closure in a first direction, when viewing the top wall, without applying a force to the exterior surface of the top wall or to the exterior surface of the first tubular wall causes the first screw threads of the second tubular wall to disengage from the second screw threads of the container.

In another embodiment, the present invention is directed to a method of manufacturing a container closure having a top wall, a first tubular wall integrally formed with the top wall and extending generally transversely downwardly from a peripheral edge of the top wall, and a second integrally formed tubular wall integrally formed with the top wall and extending generally transversely downwardly from an interior surface of the top wall radially inwardly from the first tubular wall to establish an unobstructed void between the first tubular wall and the second tubular wall. The method includes the steps of providing a single open mold, injecting a polymeric material into the single mold, allowing the polymeric material to cool until substantially solidified, and removing the single mold.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The following detailed description of the preferred embodiment of the present invention will be better understood when read in conjunction with the appended drawings. For the purposes of illustrating the invention, there are shown in the drawings an embodiment which is presently preferred. It is understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown. In the drawings:

FIG. 1 is a top perspective view of a container closure in accordance with a preferred embodiment of the present invention;

FIG. 2 is a side elevational view of the container closure shown in FIG. 1;

FIG. 3 is a bottom perspective view of the container closure shown in FIG. 1;

FIG. 4 is bottom plan view of the container closure shown in FIG. 1;

FIG. 5 is a top plan view of the container closure shown in FIG. 1;

FIG. 5A is a cross-sectional view of the container closure shown in FIG. 5 taken along line 5A-5A in FIG. 5;

FIG. 5B is a greatly enlarged cross-sectional view of the container closure shown in FIG. 5A taken about area 5B in FIG. 5A;

FIG. 5C is a greatly enlarged cross-sectional view of the container closure shown in FIG. 5A taken about area 5C in FIG. 5A; and

FIG. 5D is a greatly enlarged cross-sectional view of the container closure shown in FIG. 5A taken about area 5D in FIG. 5A.

DETAILED DESCRIPTION OF THE INVENTION

Certain terminology is used in the following description for convenience only and is not limiting. The words “right”, “left”, “lower” and “upper” designate directions in the drawings to which reference is made. The words “inwardly” and “outwardly” refer to directions toward and away from, respectively, the geometric center of the container closure and designated parts thereof. Unless specifically set forth herein, the terms “a”, “an” and “the” are not limited to one element but instead should be read as meaning “at least one”. The terminology includes the words noted above, derivatives thereof and words of similar import.

Referring to the drawings in detail, wherein like numerals and characters indicate like elements throughout, there are shown in FIGS. 1-5D a presently preferred embodiment of a container closure in accordance with the present invention. With reference initially to FIGS. 1-4, the container closure is generally designated 10.

With particular reference to FIGS. 1-5, the container closure 10 includes a top wall 12 with a peripheral or radially outer edge 12 a, an exterior or upper surface 12 b, and an interior or lower surface 12 c. The interior surface 12 c of the top wall 12 includes a plurality of concentric ribs 13 which are spaced apart from each other and which extend generally transversely downwardly from the interior surface 12 c of the top wall 12. Preferably, the interior surface 12 c includes at least three concentric ribs 13 a, 13 b, 13 c. The concentric ribs 13 a, 13 b, 13 c may be evenly spaced apart from each other. Preferably, however, the degree of spacing between each rib 13 a, 13 b, 13 c decreases in a direction leading toward the radially outer or peripheral edge 12 a of the top wall 12. A cylindrical protrusion 11 extends downwardly from the interior surface 12 c of the top wall 12, toward an interior 20 of the container closure 10, at a central longitudinal axis 10 a of the closure 10, generally, and of the top wall 12, in particular (see FIG. 4). In the ready-to-use state, the portion of the interior surface 12 c of the top wall 12 comprising the concentric circular ribs 13 a, 13 b, 13 c and the cylindrical protrusion 11 is covered with a removable disk (not shown) made of, for example, paper or cardboard, for sealing the top of a container on which the closure 10 is used.

Referring to FIGS. 1-3, a skirt or first tubular wall 14 extends generally transversely downwardly from the peripheral edge 12 a of the top wall 12. The first tubular wall 14 has a radial outer or exterior surface 14 a and a radial interior surface 14 b. The first tubular wall 14 is generally flexible, such that application of a force on the exterior surface 14 a of the first tubular wall 14 will cause an unattached distal end 14 c of the first tubular wall 14 to be deflected radially inwardly toward the interior 20 of the container closure 10. However, it will be appreciated by those skilled in the art that the first tubular wall 14 may be rigid, as flexibility of the first tubular wall 14 is not a necessary component for the container closure 10 to function.

Referring to FIG. 2, the exterior surface 14 a of the first tubular wall 14 comprises a plurality of gripping members 15 for ease of handling of the container closure 10 by a user. The plurality of gripping members 15 protrude from the exterior surface 14 a of the first tubular wall 14. Preferably, the plurality of gripping members 15 are a plurality of elongated ribs 15 that extend generally downwardly from proximate the peripheral edge 12 a of the top wall 12 toward the distal end 14 of the first tubular wall 14. The plurality of gripping members 15 provide traction for a user, such that the user is able to get a firm grip on the container closure 10 when attempting to remove it from or install it onto a container (not shown). However, it will be understood by those skilled in the art that the exterior surface 14 a of the first tubular wall 14 may alternatively be a continuously smooth surface.

Referring to FIGS. 3-4, a second tubular wall 16 extends generally transversely downwardly from the interior surface 12 c of the top wall 12. The second tubular wall 16 extends downwardly from the interior surface 12 c of the top wall 12 radially inwardly from the first tubular wall 14 and radially outwardly from the outermost concentric rib 13 c, such that the second tubular wall 16 is situated at a position between the outermost concentric circular rib 13 c and the first tubular wall 14. The second tubular wall 16 may be flexible or rigid. Preferably, the second tubular wall 16 is rigid. With particular reference to FIGS. 3-5, the second tubular wall 16 has a radial outer or exterior surface 16 a and a radial interior surface 16 b. The radial interior surface 16 b of the second tubular wall 16 includes first screw threads 18 which are matched with second corresponding screw threads formed on the container with which the container closure 10 may be used. Thus, the first screw threads 18 of the container closure 10 are configured to removably engage the second screw threads of the container with which the container closure 10 is used.

A gap or unobstructed void 17 is established between the interior surface 14 b of the first tubular wall 14 and the exterior surface 16 a of the second tubular wall 16 below the interior surface 12 c of the top wall 12. The void 17 is free of any protrusions, such as lugs or interlocks. The first tubular wall 14 and the second tubular wall 16 are formed as integral components of the container closure 10 and, therefore, there is no need for any mechanism to secure either component to the closure 10 or to each other. Specifically, the first and second tubular walls 14, 16 are integrally formed with and connected only to the top wall 12 of the container closure 10, thereby forming a double wall container closure 10 having a single-body construction. Thus, the void 17 is essentially non-functional. Further, since there is no need for any type of securing mechanism or component, the container closure 10 is simple and inexpensive to manufacture.

Rotating the container closure 10 in a first direction (e.g., a counter-clockwise direction, illustrated in FIG. 5 as the direction of arrow G), when viewing the top wall 12, rotates the first screw threads 18 on the interior surface 16 b of the second tubular wall 16 of container closure 10 out of threaded engagement with the corresponding threads of the container, causing the first screw threads 18 and the container closure 10 to become disengaged from the second screw threads of the container. The user need not apply any force to the exterior surface 12 b of the top wall 12 or to the exterior surface 14 a of the first tubular wall 14 while rotating the container closure 10. Conversely, rotating the container closure 10 in a second direction (e.g., a clockwise direction, illustrated in FIG. 5 as the direction of arrow F), when viewing the top wall 12, with or without applying force to the container closure 10, corresponds to tightening of the container closure 10 onto a threaded container.

While the container closure 10 may appear similar in appearance to a conventional double wall container closure, the container closure 10 is actually an integrally formed double-walled container closure. The container closure 10 is preferably fabricated from one or more thermoplastic or other polymeric materials using injection molding or other techniques well known to those skilled in the art. In particular, in order to manufacture the container closure 10, a single open mold need only be provided. Next, a polymeric material is injected into the single open mold to form the container closure 10. After the polymeric material has been allowed to cool until substantially solidified, the mold may be removed. Preferably, the container closure 10 is fabricated from a polypropylene or a high density polyethylene material. However, it will be understood by those skilled in the art that any polymeric materials having properties similar to polypropylene or high density polyethylene may be used.

From this disclosure, one of ordinary skill in the art would recognize that other conventional materials and fabrication techniques could be substituted. Also based on this disclosure, a person of ordinary skill in the art would further recognize that the relative proportions of the components illustrated could be varied without departing from the spirit and scope of the invention.

It will be appreciated by those skilled in the art that changes could be made to the above described preferred embodiment 10 of the container closure without departing from the broad inventive concepts thereof. It is understood, therefore, that this invention is not limited to the particular embodiment disclosed, but is intended to cover modifications within the spirit and scope of the present invention as defined by the appended claims. 

1. A closure for a container comprising: a top wall with a peripheral edge, an exterior surface and an interior surface; a first tubular wall with a radial exterior surface and a radial interior surface, the first tubular wall extending generally transversely downwardly from the peripheral edge of the top wall; and a second tubular wall with a radial exterior surface and a radial interior surface, the second tubular wall extending generally transversely downwardly from the interior surface of the top wall radially inwardly from the first tubular wall to establish an unobstructed void between the interior surface of the first tubular wall and the exterior surface of the second tubular wall below the interior surface of the top wall, the radial interior surface of the second tubular wall having first screw threads configured to removably engage second screw threads formed on the container, wherein rotating the closure in a first direction, when viewing the top wall, without applying a force to the exterior surface of the top wall or to the exterior surface of the first tubular wall, causes the first screw threads of the second tubular wall to disengage from the second screw threads of the container.
 2. The closure of claim 1, wherein the first tubular wall is flexible and the second tubular wall is rigid.
 3. The closure of claim 1, wherein the first tubular wall is rigid and the second tubular wall is rigid.
 4. The closure of claim 1 further comprising a cylindrical protrusion extending downwardly from the interior surface of the top wall at a central longitudinal axis of the top wall.
 5. The closure of claim 1, wherein the first tubular wall is connected only to the top wall.
 6. The closure of claim 5, wherein the first tubular wall and second tubular wall are integrally formed with the top wall.
 7. The closure of claim 1 further comprising a plurality of concentric and spaced-apart ribs extending generally transversely downwardly from the interior surface of the top wall.
 8. The closure of claim 7, wherein the second tubular wall extends generally transversely downwardly from the interior surface of the top wall radially outwardly from an outermost concentric rib of the plurality of concentric ribs.
 9. The closure of claim 7, wherein the degree of spacing between each of the plurality of ribs decreases in a direction leading toward the peripheral edge of the top wall.
 10. The closure of claim 1, wherein a plurality of gripping members protrude from the exterior surface of the first tubular wall.
 11. The closure of claim 10, wherein the plurality of gripping members are a plurality of elongated ribs.
 12. A method of manufacturing a container closure having a top wall, a first tubular wall integrally formed with the top wall and extending generally transversely downwardly from a peripheral edge of the top wall, and a second integrally formed tubular wall integrally formed with the top wall and extending generally transversely downwardly from an interior surface of the top wall radially inwardly from the first tubular wall to establish an unobstructed void between the first tubular wall and the second tubular wall, the method comprising providing a single open mold, injecting a polymeric material into the single mold, allowing the polymeric material to cool until substantially solidified, and removing the single mold. 